A pinhole for the laser scanning microscopy has already been suggested (DE10323921), which shall allow the setting of the pinhole size beginning at 2 μm and the setting of the pinhole position at a reproducibility of 2 μm. This should result in an improvement of the pinhole setting values compared to currently used LSM pinholes by the factor of 5. The reproducibility error of 2 μm is caused by the described step motor spindle drive and the referencing procedure of this patent. The resolution of the step motor drive is 0.3 μm (differential thread with 50 μm pitch and step motor running in ⅛ micro step operation).
A pinhole with a size of 2 μm can be used sensibly if the pinhole position can be set for a reproducibility of approx. 0.5 μm.
If the setting of the pinhole location only has a reproducibility error of 2 μm, the light hitting the small pinhole opening can be vignetted considerably.
Therefore, the invention is based on the task of improving the reproducibility of the pinhole position to an advantageous 0.5 μm.
In order to be able to achieve reproducibility of the linear movement of 0.5 μm by regular spindle drives high resolution position measuring systems are generally needed which are, however, too expensive and whose dimensions are too large for pinhole setup. Therefore, a solution is sought which will allow achieving a setting of the pinhole position reproducible to 0.5 μm without measuring systems.